soundwire: bus: fix device number leak on errors

If the programming of the dev_number fails due to an IO error, a new
device_number will be assigned, resulting in a leak.

Make sure we only assign a device_number once per Slave device.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200113225637.17313-1-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
Pierre-Louis Bossart 2020-01-13 16:56:37 -06:00 committed by Vinod Koul
parent 78f6fdd616
commit fd6a3ac8e8
2 changed files with 26 additions and 15 deletions

View File

@ -456,26 +456,35 @@ static int sdw_get_device_num(struct sdw_slave *slave)
static int sdw_assign_device_num(struct sdw_slave *slave) static int sdw_assign_device_num(struct sdw_slave *slave)
{ {
int ret, dev_num; int ret, dev_num;
bool new_device = false;
/* check first if device number is assigned, if so reuse that */ /* check first if device number is assigned, if so reuse that */
if (!slave->dev_num) { if (!slave->dev_num) {
mutex_lock(&slave->bus->bus_lock); if (!slave->dev_num_sticky) {
dev_num = sdw_get_device_num(slave); mutex_lock(&slave->bus->bus_lock);
mutex_unlock(&slave->bus->bus_lock); dev_num = sdw_get_device_num(slave);
if (dev_num < 0) { mutex_unlock(&slave->bus->bus_lock);
dev_err(slave->bus->dev, "Get dev_num failed: %d\n", if (dev_num < 0) {
dev_num); dev_err(slave->bus->dev, "Get dev_num failed: %d\n",
return dev_num; dev_num);
return dev_num;
}
slave->dev_num = dev_num;
slave->dev_num_sticky = dev_num;
new_device = true;
} else {
slave->dev_num = slave->dev_num_sticky;
} }
} else { }
if (!new_device)
dev_info(slave->bus->dev, dev_info(slave->bus->dev,
"Slave already registered dev_num:%d\n", "Slave already registered, reusing dev_num:%d\n",
slave->dev_num); slave->dev_num);
/* Clear the slave->dev_num to transfer message on device 0 */ /* Clear the slave->dev_num to transfer message on device 0 */
dev_num = slave->dev_num; dev_num = slave->dev_num;
slave->dev_num = 0; slave->dev_num = 0;
}
ret = sdw_write(slave, SDW_SCP_DEVNUMBER, dev_num); ret = sdw_write(slave, SDW_SCP_DEVNUMBER, dev_num);
if (ret < 0) { if (ret < 0) {
@ -485,7 +494,7 @@ static int sdw_assign_device_num(struct sdw_slave *slave)
} }
/* After xfer of msg, restore dev_num */ /* After xfer of msg, restore dev_num */
slave->dev_num = dev_num; slave->dev_num = slave->dev_num_sticky;
return 0; return 0;
} }

View File

@ -546,7 +546,8 @@ struct sdw_slave_ops {
* @debugfs: Slave debugfs * @debugfs: Slave debugfs
* @node: node for bus list * @node: node for bus list
* @port_ready: Port ready completion flag for each Slave port * @port_ready: Port ready completion flag for each Slave port
* @dev_num: Device Number assigned by Bus * @dev_num: Current Device Number, values can be 0 or dev_num_sticky
* @dev_num_sticky: one-time static Device Number assigned by Bus
* @probed: boolean tracking driver state * @probed: boolean tracking driver state
* @probe_complete: completion utility to control potential races * @probe_complete: completion utility to control potential races
* on startup between driver probe/initialization and SoundWire * on startup between driver probe/initialization and SoundWire
@ -575,6 +576,7 @@ struct sdw_slave {
struct list_head node; struct list_head node;
struct completion *port_ready; struct completion *port_ready;
u16 dev_num; u16 dev_num;
u16 dev_num_sticky;
bool probed; bool probed;
struct completion probe_complete; struct completion probe_complete;
struct completion enumeration_complete; struct completion enumeration_complete;